A REVIEW OF THE MATONIACEAE BASED ON IN-SITU SPORES

Fossil and extant matoniaceous spores in situ have been studied by LM and SEM. The extant material comprises Matonia pectinata and Phaneroso rus sarmentosus, the fossil material comprises those species of which the spores are known from the genera Phlebopteris, Matonidium, Matonia , Selenocarpus, Nathorstia, Piazopleris, Delosorus and Weichselia. Sev eral spore types could be distinguished, based on spore size, absence or presence of interradial and apical thickenings, thickness and sculp ture of the exospore and absence or presence of a perispore. The peris pores of the extant species proved to be more elaborate than those of the fossil material. Comparison with dispersed fossil spores has been made. Also brief taxonomic studies on the megafossils have been carrie d out, leading to the reinstallation of Phlebopteris affinis Schenk (i ncluded in P. polypodioides by Hirmer and Horhammer, 1936) and the new combinations Matonia brownii (Rushforth) nov. comb. and Nathorstia ga lleyi (Miner) nov. comb. Furthermore, Nathorstia angustifolia Heer has been made the type species (lectotype) of the genus Nathorstia.